Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Re: If N, C, and D are positive integers, what is the remainder [#permalink]

Show Tags

06 Nov 2012, 18:54

1. insufficient b/c D and C can be any number. adding +1 can change remainder completely. ex: D =2 , C = 3 R = 2 ... D = 2+1 , C = 3+1 R = 3 2: sufficient b/c (ND + NC)/CN => ND/CN + NC/CN => ND/CN =>D/C + 1 => R5

Re: If N, C, and D are positive integers, what is the remainder [#permalink]

Show Tags

14 Oct 2014, 13:11

1) insufficient 2) ND+NC/CN gives a remainder of 5.

ND + NC / CN = (D+C)/C

So we know that (D+C)/C gives a remainder of 5.

The idea here is that if you add any multiple of C to C then you will definitely get a multiple of C. For eg. 4 is a multiple of 2. So (4+2)/2 will give R=0. In this case though we have a number added to C leaving a remainder of 5. This means that D is not divisible by C and that D must leave a remainder of 5. Eg. (5+0)/10 leaves a remainder of 5 . (5+10)/10 will leave a remainder of 5 also. So the remainder will always be in D in the equation (D+C). This means that D/C will also give us a remainder of 5. Sufficient.

Re: If N, C, and D are positive integers, what is the remainder [#permalink]

Show Tags

28 Oct 2014, 12:10

Well, I am confused here and need some help.

I chose D.

Reason is as follows: For statement A: take D+1=12 and C+1=7 so 12/7 => remainder 5 if we take 11/6 => remainder is still 5

In the explanation above for D=CK + (K + 4), for different values of K, we are actually changing the value of D while keeping the value of C same. If the algebra calculations are correct and logic is correct, there must be some example to support this explanation.

Re: If N, C, and D are positive integers, what is the remainder [#permalink]

Show Tags

04 Nov 2014, 02:55

VeritasPrepKarishma wrote:

kingb wrote:

If N, C, and D are positive integers, what is the remainder when D is divided by C?

1) If D+1 is divided by C+1, the remainder is 5. 2) If ND+NC is divided by CN, the remainder is 5.

Stmnt 1: If D+1 is divided by C+1, the remainder is 5.

D+1 = (C+1)k + 5 D = Ck + (k + 4) When D is divided by C, the remainder will vary with k. If k = 0, remainder will be 4 (C is greater than 4) If k = 1, remainder will be 5 (C is greater than 5) If k = 2, remainder will be 6 (C is greater than 6) etc

2) If ND+NC is divided by CN, the remainder is 5. ND + NC = CN*k + 5 DN = CN*(k-1) + 5 D = C*(k-1) + 5/N Now, N is a positive integer and remainder must be a positive integer too. The only value that N can take such that 5/N is a positive integer is 1. So N must be 1. D = C*(k -1) + 5 When D is divided by C, remainder is 5.

Answer (B)

Sorry to bother , I just want to ask ... N can't be 5 ? 5/N will still be integer i.e. 1 Could you please explain why only value N can take is 1?

Re: If N, C, and D are positive integers, what is the remainder [#permalink]

Show Tags

04 Nov 2014, 21:03

Expert's post

1

This post was BOOKMARKED

anupamadw wrote:

VeritasPrepKarishma wrote:

kingb wrote:

If N, C, and D are positive integers, what is the remainder when D is divided by C?

1) If D+1 is divided by C+1, the remainder is 5. 2) If ND+NC is divided by CN, the remainder is 5.

Stmnt 1: If D+1 is divided by C+1, the remainder is 5.

D+1 = (C+1)k + 5 D = Ck + (k + 4) When D is divided by C, the remainder will vary with k. If k = 0, remainder will be 4 (C is greater than 4) If k = 1, remainder will be 5 (C is greater than 5) If k = 2, remainder will be 6 (C is greater than 6) etc

2) If ND+NC is divided by CN, the remainder is 5. ND + NC = CN*k + 5 DN = CN*(k-1) + 5 D = C*(k-1) + 5/N Now, N is a positive integer and remainder must be a positive integer too. The only value that N can take such that 5/N is a positive integer is 1. So N must be 1. D = C*(k -1) + 5 When D is divided by C, remainder is 5.

Answer (B)

Sorry to bother , I just want to ask ... N can't be 5 ? 5/N will still be integer i.e. 1 Could you please explain why only value N can take is 1?

Actually it can take value 5 too. I will rewrite the solution given above soon. _________________

Re: If N, C, and D are positive integers, what is the remainder [#permalink]

Show Tags

04 Nov 2014, 21:15

Expert's post

nnitingarg wrote:

Well, I am confused here and need some help.

I chose D.

Reason is as follows: For statement A: take D+1=12 and C+1=7 so 12/7 => remainder 5 if we take 11/6 => remainder is still 5

In the explanation above for D=CK + (K + 4), for different values of K, we are actually changing the value of D while keeping the value of C same. If the algebra calculations are correct and logic is correct, there must be some example to support this explanation.

We all agree to sufficiency of statement B.

Please advise.

In statement 1, say if C+1 = 8 and D+1 = 21, remainder is 5. C = 7 and D = 20, remainder is 6. Not sufficient alone. _________________

Part 2 of the GMAT: How I tackled the GMAT and improved a disappointing score Apologies for the month gap. I went on vacation and had to finish up a...

Cal Newport is a computer science professor at GeorgeTown University, author, blogger and is obsessed with productivity. He writes on this topic in his popular Study Hacks blog. I was...

So the last couple of weeks have seen a flurry of discussion in our MBA class Whatsapp group around Brexit, the referendum and currency exchange. Most of us believed...